I have a very large property, long driveway and alot of brick pattio that
has gotten really out of control with weed overgrowth.

Is there a super-concentrated chemical that I can buy to mix with water that
will kill the weeds in the driveway and between the bricks but leave the
grass alone?

remember...big property, and I need a concentrate that won't bleed my wallet
dry.

Thanks,
Bob